Contents:

• How works this module?
• Requirements
• What contains this module?
• What must I implement?
• How use it?
• State of the module and future updates.

How works this module?

Requirements

This module require external dependencies:

• Paho-mqtt library for python (install with pip).
• A Broker server (like Mosquitto)

What contains this module?

This model only contains two files:

Main.py:

This python file acts as a controller for the MqttAbstractInterface model, it contains all the methods necessaries to connect to a broker and subscribe to topics.

The controller start a thread, that receives "tasks" from the model (subscribe, publish, connect, etc..) and put them in a queue where they are executed one by one by the model.

Mqtt_abstract_interface_model.py:

This file contains the MqttAbstractInterface class (the abstract model) that is inherited by another's models. This class has 3 methods that requires implemententation:

• on_message(self, client, userdata, msg):

  This method is a callback executed when there are a incoming message from a topic, this message contain a payload (msg.payload) that must by processed in this method to extract the necessaries parameters and pass it to the "create record" method.

• create_record(self, values):

  This method is responsible for the creation of records in the database, from the "values" dictionary that contains the data needed for the model.

• mqtt_publish(self, toic, message):

  This is a optional method for adding functionalities to the original "publish" method (It's necessary include the original method)

What must I implement?

In addition to the methods already mentioned it's necessary serve the broker and create an automated action with the model that inherit the abstract interface which includes the followings methods:

• action_start_mqtt(self):

  This method initiates the mqtt client in a thread and starts a connection with the broker. The defaults values are:

  Server : locallhost

  Port : 1883

  Ttl :60

  The changes in this values must be done directly in the font code.

• subscribe(self, topic):

  This method subscribes the client to a topic, the "topic" parameter is optional, with default value '#' (for subscribe to all topics.

How use it

It can be easily initialized:

1. Download and install paho-mqtt library.
2. Extend your custom model with the abstract interface.
3. Implement the methods previously described.
4. Create automatized actions to start Mqtt and subscribes topics

State of the module and future updates.

• Multi connection to brokers and a manage wizard for its.
• Auto creation of the automatized action.